SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efeac6d0078f2442ce8fdd13c5a5ee9b6b888679c6c3dc5b3fbe7828ff6bd8d1' 
  AND token = 'gnQbu9OvpxYUu8JzBfTjAUJwKtdqwMMMgKhQnyW4Ewk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}